Diaphragm



H. W. JOY

DIAPHRAGM Filed April 192s INVENTOR M BY 41 ATTORNEY.

Patented Dec. 21. 1926.

unirso STATES HENRY W. JGY, OF NEW YORK, N.'Y.

DIAPHRAGM.

Application filed ApxiltZlQlQfZS. Serial No. 24.779.

lily invention relates to iinproveincntsin cliapln'agms such as arecommonly employed in sound reproducing apparatus The principal object ofthe invention is to provide at diaphragm of this character which may heused in connection with telephones. radio loud speakers, and the like.

A further object of the invention is to provide means LO securevibrations of the diaphragm that will in their entirety synchronize "lywith the highest to the lowest values or? the modulnted currentoperating the customary elcctrc-n'ingnet commonly employed to no tediaphragm.

lt has been found necessary to increase the resilience or s gringinessoi the diaphragm us common 3' used in radio loud speakers and the like,so that the spring recoil of the diapl'llfelglll shall have :1 highervelocity or nuinher of vibrntionsiper second than prevail in all. highpitched audible sounds. If the resilience of any diaphragm is of aslower period than the pulsations of the operating or voice carryingcurrent, then the fatigued areas oi the diaphragm will lag behind thevibrations up at and near the center of the diaphragm. 'lihe center ofthe diaphragm by reason of its receiving the great- 9 t impulse from themagnet will respond to the pull or release or the latter. before theconcentric regions thereof between the center of the edge have had timeto vibrate in harmen with the increment set up st'the centeix.

With the abovein mind the present in vention coinprehends a diaphragmcapable of having simultaneous movements over the entire surface,accomplish this result by impressing a series of ridges, radiating fromthe center and preferably diminishing in cross section as they approachthe edge. I have found that an odd or even number of ridges may beemployed, but the ridges should by preference be equidistant, the onefrom the other. Disphragn'is according to the present invention may bepressed from metal, glass any resilient substance, the overall diameterthereof conforming to the requirements of service. It will be clear thatthe gauge of the diaphragm will vary according to the material used asWell as the relative diameter.

In practice 1' have found it preferably to impress identically formedradiating ridges which approach each other, and a common center, near asis mechanically possible.

Una embodiment of my improved diaa plan elevstional view of the cannotaccommodate the inner or r mitted simulteneonsly to the entire snrphragmis illustrotively cncinglified. accompanying drawings, in whn Fig.taken on the line 2-2 of Fig. l; and l 3 is a transverse sectional Viewthrough one of the ribs of the diaphragm.

Referring to the drnWings l0 den diaphragm proper which comprises a.having a plurality of uniformly spac dial ridges l1 impressed therein.The maphragzm is supported between annular memhers l2 and vibrated lcymeans of an electromagnct 18.

As the actual center the diiziphragm 1'3 ends of the ridges, the centeris apex of the cone is directed towers troenagnet l3 and carries itn'ojection. 15 preferably of soft 29 which is disposed within the ningneold of the electro-inagnet 13. it is'n' chsc nt v necessary to m depressthe diaphragm center to form a cone shaped portion becaiise any dec'shape may he used, the object to p Vent the actual center from.vibrating colors any other portion the diaphragm. The comically shapedcenter l lis me'rel ed in order to strengthen the act of the din hrag'znwhich must transmit Vi a ations to al the ridges in unison hecsuse, asthe ridges vibrate so each vibrstion is firs of the dinphragn'i, thuspreventing or :t'nti ue.

It Wlll be clear "lint the travel or oscillotions of the diaphragm willbe greatest and near the center, and such oscillations will diminish asthe edge of the diaphragm is approached. concentrically.

The operation of the diaphragm is as fol lows :-The center of thediaphragm. receives an impulse from the magnet 13. The deflection isthen transmitted direct and Without loss of time to all the ridges whichin turn carry the fiat or plane stress of the diaphragm with them, so asto bring the whole area of the diaphragm into vibration in absoluteunison to the magnetic impulse. The ridges 11 by virtue of their." shaperesist all movement other than a rise and fall in a plane at rightangles to the plane of the diaphragm l0.

\Vhat I claim is 1. Anacoustical diaphragm of "resilient a plurality ofimpressed depression to a line short of the periphery of a from near thecentre of the the diaphragm, said ridges being widest at gni bewards itsperiphery, said ridgee-suid conical depression and gradually degraduallydereasing cross section-creasing in cross section to the Vanishing i thecentre tewerd theperiphery of the point toward the periphery of the dia-15 aiiaiyii-egmi phragm. v I v All acoustical diaphragm of resilient Intestimony whereof I have afiixed my eteriel having a conical depressionatits signature.

ifentre and a pluraiity of equidistantly spaced" I i e impreesed ridgesradiating from the conical HENRY XV JOYV

